What is the least-expensive way to get a practice box for MacOS practice?

I'm looking to get into doing tech support for a school district or community college, but all of the ones I've seen so far insist on MacOS proficiency or want it strongly enough that it's a serious competitive advantage over other applicants without it. So I need to pick up something that can run the latest version of MacOS.

However, I also know that Apple tech tends to be expensive. What's my best option for snagging an Apple device I can acquire proficiency on without spending a fortune?

I don't care if it's portable or not, I just have no idea what models to look for or how much to budget.

You can run Mac OS in a virtual machine on Windows. Last I remember, VMWare has a consumer version that is free that would work.

More costly than that would be a hackintosh or an old Mac Mini.

VirtualBox does that too.